Tractor track



Sept. 13, 1949. J. L. DEFFENBAUGH TRACTOR TRACK 2 Shets-Sheet 1 FiledJune 3, 1946 INVENTOR. d014,? L. fl yena 11 /4 ATTORNEY Sept. 13, 1949..L L. EFFENBAUGH TRACTOR TRACK Filed Juri 5, 1946 2 Sheets-Sheet 2 EYE EIN VEN TOR.

Patented Sept. 13, 1949 TRACTOR TRACK.

John L- ugh Caterpillar Tractor (30., San

corporation of California ri 1 1- assisnq o Leandro, Califi, a

Application June 3, 1946. Serial No. .(i7 l ,Q(j8

1 Claim.

The present invention relates to tracks for track-type tractors or othersimilar vehicles and pertains particularly to the track pins or pivotalconnections between the shoes which make up the tracks.

Owing to. he severe nature of the serv ce to which tracks are subjectedand t the environment in which they operate, the pivotal bearinconnections between the track shoes constitute points at whichconsiderable wear takes place. Ordinary methods of lubricating bearingsand pivotal connections have not proven successful in overcomingexcessive wear at these .points as dust and other abrasives have anaffinity for oil and grease and in man cases the lubricant acts s acarrier for the abrasive substances through which the tracks operate andtherefore increases rather than reduces the wear which takes place. Thetrack shoes are necessarily constructed of a relatively soft ormalleable material to withstand service which would be destructive toharder brittle materials. The track pins which are necessarily of hardsteel or the like therefore Wear into the metal of the shoes and theloose fit which results effects imperfect operation and eventuallybreakage or failure.

, It is an object of the invention to overcome the foregoing and otherdisadvantages of conventional tractor tracks and to provide an improvedtrack of simple and durable construction which embodies -a floatingtrack pin operating against hard surfaces and protected against theabrasive action of dust and other foreign material. Further objects andadvantages of the invention are made apparent in the iollowingspecification wherein reference is made to the accompanying drawings.

In the drawings:

Fig. 1 is a plan view of a portion of a tractor track illustrating threeof its track shoes which are pivotally connected together by a hingejoint constructed in accordance with the present invention, parts of theView being broken away to clarify the illustration;

Fig. 2 is a view in side elevation of the structure illustrated in Fig.1;

Fig. 3 is an enlarged vertical transverse sectional View taken on theline IIIIII of Fig. 2;

Fig. i is an enlarged fragmentary section illustrating a modification ofa portion of the structure shown in Fig. 3; and

Fig. is a similar view illustrating a further modification of the sameportion.

The track of which a portion is illustrated in Figs. 1 and 2 is made upof a plurality of track shg H! which a hin or pivo ally c nn cted. Witheach other as by track pins ll so that a complete et of track sho s ay man endless chain of track shoes adapted to be trained over a drivesproclret and an idler sprocket as is cuss ernary to form the trackassembly of a track, ime tract r or similar vehi e,

Bas 0f the tr ck hoes 1n erei i strat d is te m a a ub tantia l a la Pate which has par le sp ock t guide eb l n t back su fage n u s 13 disped. bet r Said Web for en a em nt by t e ee a entional drive sprocket.Each of the tracl; shoes t m y al o b o i ed t round ng in iss, on its oo it sid an w t su tab e ref nio cins bs uch are d cat at 51 Th ceastruii n a d a rang me o these e era parts may vary without affecting theadvantages hat r pro ded y the i ge nne t of 3.6 present- 1E92 Eac ofthe r 9 ce s rov d d with a in e time 1 "5 t e g its nd and a sew d ei.I 1 h n e s t rp it end allgf i a H5 nd 1 being bo d i r eception of thetrack pin [I by means of which he's r hin n i dau e 1 ew ha h trees 98 ih ei mass en i ns r ie'o 'e t e ro d d e subjected to mud, dust, andother abrasive ma.- terials which make up the environment in which theyoperate, these hinged connections have given rise to considerabledifficulty. The present invention provides means for permitting thehinged pins H to float freely under conditions where they are sealedagainst the entry of foreign matterwhich might be destructive to theirhearing engagement with the track shoes.

As is most closely illustrated in Fig. 3, the hinge lugs l! of eachtrack shoe are provided with press fitted bearing bushings l8 whichprovide a bearing for the end portions of the pin II. The single hingelug l6 of the adjacent track shoe is provided with a press fittedbearing bushing is which also receives and supports the hearing pin lladjacent its central portion. The bearing bushing I9 is somewhat shorterthan the hinge lug it so that it may be centrally positioned. therein,leaving spaces between each of its ends and the ends of the lug [6. Thebearing bushings 13 have slightly reduced inner end portions arranged toproject into said spaces at the ends of the bearing lug IE to provideannular channels shown at which extend from the abutting surfaces of thelugs l6 and I! to the abutting ends of the bushings l8 and 19. Be-

closed against the entry of abrasive substances preferably by plugs 21press fitted and frictionally retained therein. These plugs areinexpensive pressed metal parts which may be pierced and pried out withany suitable tool when their removal becomes necessary. As the track pinis freely rotatable with relation to all of the bearing bushings l8 andI9 it is also free to float or move longitudinally and such movement islimited by stop pins 22 which, as shown in Figs. 1 and 3,

are pressed through suitable holes formed in positions intercepting thehinge pin bores in the hinge lugs 11. The pins 22 are preferablyinserted downwardly, or from the upper surfaces of the track shoes asthey are illustrated in Fig. 3, and may be either tapered or straightand are frictionally retained in place. If desired, slightly smallerbores, shown in dotted lines 220,, may be continued through the lowersurfaces of the track shoes to enable the pins to be driven upwardly andout of place when it is desired to I remove them for the purpose ofdisassembling the track. An advantage of the arrangement of the stoppins herein shown is that they act by engagement with the'ends of thetrack pins H and therefore do not interfere with the floatingdisposition of the pin I l and do not require the pin to be bored orshouldered in any manner which would tend to, weaken it.

A modified form of seal designed for use adjacent the abutting ends ofthe hinge lugs l6 and I1 isillustrated-in Fig. 4 wherein both thebearing bushings Ifland I9 are shown as terminating short of the endsofthe hinge lugs to provide recesses for the reception of conventionalsealing members 29. The members 29 are made up of annular metal cases ofchannel shaped cross section press fitted into the ends of the hingelugs l6 and l I and containing suitable packing shown at 30 forengagement with the surface of the track pin H.

A still further modification of this sealing means is illustrated inFig. 5 in which the spaces between the ends of the bearing bushings l8and I9 and their respective hinge lugs l1 and 16 contain annular sealsof rubber or similar resilient 4 material shown at 31. Each resilientsealing member 3| is disposed between metal rings 32 and 33 to which itis securely bonded. The rings 32 are press fitted into the bores of thelugs l6 and il and the rings 32 are similarly fitted close contact withthe outer surface of the hinge pin H. The slight pivotal movementnecessary for the operation of the structure is made possible by theresilience of the resilient substance 3! and the actual bearing surfacesof the pin II are protected against the entrance of abrasiv materials.

With the invention herein described, the hinge pin H has free bearingcontact with the hardened bushings l8 and I9 and as abrasive substancesare prevented from entering the areas of such contact bearing wear isreduced to a minimum. The hinge connection between the track shoes maybe operated as herein illustrated without lubricant or it may beassembled with lubricant and a supply of lubricant may be contained inthe spaces between the ends of the bearings pins 1 land the plugs 2|which close the open ends of the hinge lugs I1.

I claim:

A hinge connection between shoes of a tractor track which comprisesspaced hinge lugs on one shoe, a singlehinge lug On an adjacent shoe forreception between the hinged lugs, said lugs having aligned bores,bushings fitted in the bore of each lug, a floating track pin extendingthrough the lugs for bearing engagement with said bushings andterminating short of the outer ends of said spaced hinge lugs to providespaces for a supply of lubricant in the lugs, plugs sealing said spaces,and stop pins extending through said spaces adjacent the ends of thetrack its longitudinal floating movement.

JOHN L. DE'FFENBAUGH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Great Britain Aug. 3, 1933 pinto limit

